对换改变排列奇偶性的一个定量证明

A Quantative Proof of Swap Changes the Sign of a Permutation

先对排列逆序及逆序数的概念进行拓展,然后再给出关于对换改变排列奇偶性这个定理的一个定量证明.

We extend the notion of the permutation inversions and the number of permutation inversions in the article, and then we get a quantative proof of the well-known theorem that swap changes the sign of a permutation.